Recombination Signal Sequences Are Conserved Heptamer and Nonamer Sequences That $\kappa$

question 33

Multiple Choice

Recombination signal sequences are conserved heptamer and nonamer sequences that flank the V, J, and D gene segments which undergo recombination to generate the final V region coding exon. Some of these have 12-nucleotide spacers between the heptamer and nonamer, and others have 23-nucleotide spacers. The reason recombination signal sequences come in these two forms is:

• A) To ensure the correct assembly of gene segments so that a V_H recombines to a D_H and not to another V_H, for instance
• B) To ensure that the heptamer and nonamer are found on the same face of the DNA double helix
• C) To ensure that \(\kappa\) , \(\lambda\), and heavy chains recombine within a locus and not between loci
• D) To ensure that \(\kappa\) , \(\lambda\), and heavy chain gene segments do not undergo recombination with non-immunoglobulin genes
• E) To ensure that the RAG recombinase cuts the DNA between the last nucleotide of the heptamer and the coding sequence

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Definitions:

Exogenous

Originating from outside an organism or system.

Brain

The central organ of the human nervous system, responsible for processing information and controlling bodily functions.

Agonist

A substance that activates a receptor to produce a biological response.

Antagonist

in pharmacology, a substance that acts against and blocks an action. In literature, a character or force in conflict with the main character.